<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>圣杯模型</title>
</head>
<body>
    <style>
        *{
            margin: 0;
            padding: 0;
            background-color: #000;
        }
        .navbar{
            width: 100%;
            height: 50px;
            background-color: rgb(144, 41, 41);
            color: rgb(255,255,255);
            font-size: 20px;
            text-align: center;
            line-height: 50px;
        }
        .parent{
            width: 100%;
            height: 1000px;
            background-color: antiquewhite;
            display: flex;
            justify-content: start;
            align-items: center;
           
        }
        .parent .left,.parent .right{
            width: 20%;
            height: 100%;
            background-color: rgb(36, 140, 81);
            color: rgb(255,255,255);
            font-size: 20px;;
            text-align: center;
            line-height: 1000px;
        }
        .parent .content{
            width: 60%;
            height: 100%;
            background-color: grey;
            color: rgb(255,255,255);
            font-size: 20px;;
            text-align: center;
            line-height: 1000px;
        }
        /* .footer{
            width: 100%;
            height: 100px;
            background-color: rgb(144, 41, 41);
            color: rgb(255,255,255);
            font-size: 20px;;
            text-align: center;
            line-height: 100px;
        } */
    </style>
    <div class="navbar">我是导航栏</div>

    <div class="parent">
        <div class="left">我是左边栏</div>
        <div class="content">我是内容栏</div>
        <div class="right">我是右边栏</div>
    </div>
    <!-- <div class="footer">我是页脚</div> -->
</body>
</html>